The X30 is really good, full features and cheap. That's Dell's motto: make them in large quantity and make them cheap. Oh, you asked why you can't find Dell in any store, because Dell does direct sales only (you can only buy online if you are a consumer). They send their sales reps to corporations to sell volumes.
Pocket PC can deal with Wifi security in similar ways as laptops. If you have the wifi network's info like IP addresses and security settings, you should be able to access the wifi just like your laptop (login) with the Dell.